OB Hemorrhage Relias 2025–2026: 40+ Expert-Curated Verified Q&A with Emergency Response Protocols, Pharmacological Management & Postpartum Clinical Scenarios (RN/NP/CNM Aligned + Instant Digital Access)

What percentage of births are affected by OB hemorrhage?

OBH is responsible for how many pregnancy related deaths worldwide?

11% of births

25% of pregnancy deaths worldwide, 10.7% in the US

4 domains of care?

- Readiness (hemorrhage cart, training, protocols)

- Recognition/prevention (risk assessment, accurate EBL)

- Response (standard plan)

- Reporting (debriefs/reviews)

OB Hemorrhage protocols have been shown to decrease maternal death rate by ___ and maternal morbidity by ___.

OB Hemorrhage protocols have been shown to decrease maternal death rate by 50% and maternal morbidity by 21%.

Stages of Hemorrhage

Stage 0 - active mgt 3rd stage

Stage 1 - >500 vaginal, >1000 CS: activate OBH protocol

Stage 2 - 1000 - 1500 QBL, advance through protocol sequentially

Stage 3 - >1500QBL: activate MTP, move to OR

Stage 4 - cardiovascular collapse

Uterotonics and dosages

TXA

Oxytocin: 10-40 units per 500-1000cc IV, or 10 units IM.

Methergine: 0.2mg IM q2-4h (avoid if HTN)

Carboprost: 0.25mg IM q15-90 min, no more than 8 doses =2mg. (avoid if significant asthma)

Misoprostol: 800mcg SL or PO x 1

TXA (not uterotonic): 1g (100mg/mL) infused over 10 min, can repeat at 30 min

Risk factors for OB Hemorrhage

-History of OBH

-Uterine overdistension (multiple gestation, large fibroids, macrosomia, polyhydramnios)

-Grand multiparity or Primiparity

-Obesity (inc atony)

-Prior CS / Uterine surgery

-Abnormal placentation

-Abruption

-Coagulopathy/ Bleeding Disorder

-Personal or FHx OBH in a 1st degree relative

Platelets <100k

-Prolonged or augmented labor

-Prolonged third stage

-Operative Delivery

-Connective tissue disorders

-Preeclampsia/HELLP

-Use of MgSO4

-Malpresentation (inc risk of trauma)

-General anesthesia

Recurrence risk of OBH?

ranges 8-28% depending on contributing factors

May be as high as 80% in patients with vWF disease

High risk factors for OBH include:

Previa/low lying placenta

Accreta spectrum

Hct <30 + other risk factor

Platelets <100k

Active bleeding on admission

Known bleeding d/o

Multiple lower level risk factors

TYPE AND CROSS these peeps

Signs/symptoms of hypovolemia and concealed hemorrhage to tell patients?

dizziness, rapid HR, fatigue, rectal or pelvic pressure, abdominal pain

Atony is the cause of OBH at delivery in about ___% of cases.

About ____% of OBH is secondary (late).

80% atony

1-3%, rarely atony

When does primary and secondary hemorrhage occur?

Primary (early): within 24h of delivery

Secondary (late): 24h - 12 weeks after delivery

Women who deliver by primary CS have a ___% chance of subsequent CS.

90%

Women over 40 statistics:

2x as likely as moms <20yo to have a CS.

death rate 81.9 per 100k births

7.7x more likely to die of pregnancy than women <25yo

Physiologic cardiovascular changes of pregnancy peak at ___weeks.

Plasma volume expands by ____% while red cell volume increases by ____%, resulting in maternal ______.

Physiologic cardiovascular changes of pregnancy peak at 32 weeks.

Plasma volume expands by 40-50% while red cell volume increases by 20-30%, resulting in maternal anemia.

Clinical signs of maternal blood loss such as tachycardia and hypotension may not appear until _____% of circulating blood volume is lost.

Tachycardia: 15-20%

(1000-1500cc)

Hypotension w/tachycardia: 25-40%

(>2000cc)

What is the rate of uterine blood flow at term?

up to 750cc/min

(10-15% of maternal cardiac output)

3 mechanisms that control uterine bleeding at delivery:

-Contractions compress blood vessels

- Tissue factor is released from the decidua (combines with FVIIa to initiate the extrinsic clotting cascade)

- Circulating clotting factors including platelets, fibrinogen form clots at the uterine blood supply

What factors increase clotting?

What factors decrease clotting?

Increase: 5,7,8,9 and thrombin

Decrease: C, S, plasmin, antifactor Xa, antithrombin 3

What makes pregnancy a hypercoagulable state?

Increased clotting factors

Decreased anti-clotting factors

What is the shock index and its relevant cutoff?

Shock index = HR/SBP

Sensitive indicator of blood loss

>=1.4 requires urgent intervention

What is the lethal triad of excessive hemorrhage?

Hypothermia (halts coagulation)

Coagulopathy (increases lactic acidosis)

Acidosis (decreases myocardial performance)

Calcium, lactate, base deficit, temperature goals?

Ca >2

Lactate <2

Base Deficit <3

T 96.8-99.5

1 cc blood weighs ___.

1 cc blood = 1 gm

Types of peripartum hematoma?

Risk factors for developing?

Vulvar, vulvovaginal, paravaginal, retroperitoneal

Risks: nulliparity, episiotomy, forceps delivery

What are the processes in DIC?

Consumptive coagulopathy:

- Triggering event releases TF (thromboplastin), activating clotting cascade

- Platelets and clotting factors are used up > Bleeding

- Intravascular clots cause end-organ damage

Amniotic fluid embolism is also called ______.

What is the cause?

What is the maternal triad?

What are the two phases?

AFE = ASP (Anaphylactoid syndrome of pregnancy)

- maternal immunologic reaction to fetal antigens entering maternal circulation during labor/delivery, causing release of excessive catecholamines

Triad: hypovolemia, hypotension, coagulopathy

Phase 1 - cardiopulmonary phase

Phase 2 - late hemorrhagic phase (DIC)

How should oxytocin be used for active management of the third stage?

Give 10 units within 30 min (can be diluted in IVF or given IM)

Continue at 10 units per hour for 4 hours

Can give 10 - 40 units in 1000 mL saline

Up to 80 units in 1000mL can be given, but no extra benefit is shown

What is the mechanism of methergine?

Dosing?

Contraindications?

Alpha-adrenergic agonist that causes vasoconstriction

IM - 0.2mg, 2-5 min effect

PO - 0.2mg, 5-10 min effect

Intrauterine (can be transabominal) - 0.2mg, 2-5 min

AVOID IF: preeclampsia/HTN, Raynauds, scleroderma, CAD, or on protease inhibitors

What is the mechanism of prostaglandin F2-alpha?

Dosing?

AKA Hemabate / carboprost

IM or Intrauterine - 0.25mg

Given every 15 - 90 min to a max of 2 mg (up to 8 doses)

Must be refrigerated

AVOID if active asthma requiring treatments

What is the mechanism of prostaglandin E1?

Dosing?

AKA Cytotec / misoprostol

SL, PO, Rectal - 400-800mcg

How does TXA work? Dosing?

inhibits fibrinolysis by competitively blocking plasminogen activation on the surface of fibrin (clots can't break down)

Opposite of tPA, which activates plasmin from plasminogen

1g in 100mL over 10 min, can give another 1g after 30 min

What is a uterine tourniquet?

A method to reduce blood loss at the time of laparotomy

A foley catheter is tied tightly around the lower uterine segment for vascular occlusion

What is a good indicator that uterine compression sutures will be effective?

If manual compression of the uterus slows bleeding

What is an O'Leary stitch?

Compresses the uterine artery to the uterine wall just above the level of the cervix

What is a pelvic pressure pack?

A sterile tamponade device used after hysterectomy in the setting of coagulopathy, placed into the general pelvis through the open vaginal cuff

What vital signs criteria are used to transfuse prior to return of labs?

QBL 1000cc or more

HR 110 or more

BP < 85/45

Ongoing bleeding with a negative clot tube

Unstable vitals

What is the transfusion Hb level for a patient who has STOPPED bleeding?

8 mg/dL

What does the INR tell you about clotting factors?

INR 1.6 suggests that clotting factors are at 30% of their normal level, and FFP may be needed

3-6 units of FFP required to increase clotting factors by 20%

1 unit FFP raises fibrinogen 10mg/dL

What is the usual dosing of cryoprecipitate?

1 unit per 10kg body weight

Criteria for activating MTP?

Stage 3 cumulative blood loss >1500cc

2u PRBC given with persistent hemodynamic instability

Coagulopathy

Anticipated EBL 50% or more of total blood volume in 2h

Persistent bleeding after 4u PRBC

Uncontrolled bleeding with maternal hypovolemia

What is ANH?

Acute normovolemic hemodilution

1L blood drawn immediately before surgery and replaced with 1L crystalloid

Person's own blood transfused back after surgery

Point is to reduce loss of RBCs by diluting